In-situ Ultrafast Construction of Zinc Tungstate Interface Layer for Highly Reversible Zinc Anodes.

Constructing artificial solid electrolyte interface on the Zn anode surface is recognized as an appealing method to inhibit zinc dendrites and side reactions, whereas the current techniques are complex and time-consuming. Here, a robust and zincophilic zinc tungstate (ZnWO4) layer has been in situ constructed on the Zn anode surface (denoted as ZWO@Zn) by an ultrafast chemical solution reaction. Comprehensive characterizations and theoretical calculations demonstrate that the ZWO layer can effectively modulate the interfacial electric field distribution and promote the Zn2+ uniform diffusion, thus facilitating the uniform Zn2+ nucleation and suppressing zinc dendrites. Besides, ZWO layer can prevent direct contact between the Zn/water and increase the hydrogen evolution reaction overpotential to eliminate side reactions. Consequently, the in-situ constructed ZWO layer facilitates remarkable reversibility in the ZWO@Zn||Ti battery, achieving an impressive Coulombic efficiency of 99.36% under 1.0 mA cm-2, unprecedented cycling lifespan exceeding 1800 h under 1.0 mA cm-2 in ZWO@Zn||ZWO@Zn battery, and a steady and reliable operation of the overall ZWO@Zn||VS2 battery. The work provides a simple, low cost, and ultrafast pathway to crafting protective layers for driving advancements in aqueous zinc-metal batteries.

High-Rate and Ultra-Stable aqueous Zinc-Ion batteries enabled by Potassium-Infused ammonium vanadate nanosheets.

Aqueous zinc-ion batteries (AZIBs), defined by low expenses, superior safety, and plentiful reserves, demonstrate tremendous development potential in energy storage systems at the grid scale. Whereas the cathode instability and the limited diffusion of Zn2+ have impeded the development of AZIBs. Herein, a high-performance K-NH4V4O10 (K-NVO) cathode with K+ doping synthesized successfully through one-step hydrothermal approach. Experiments and density functional theory (DFT) calculations indicate that K-NVO has Zn2+ diffusion pathways with lower barriers for smoother transport, and lower formation energy. The combination of the rapid Zn2+ diffusion and the stable structure results in outstanding electrochemical performance of K-NVO as demonstrated in tests. K-NVO cathode achieves a specific capacity of 406 mAh g-1 at 0.2 A g-1, maintains satisfactory cyclic stability with 81.6 % capacity retention after 1000 cycles at 5 A g-1, and possesses a high energy density of 350.9 Wh kg-1. Furthermore, confirmation of the zinc storage mechanism in K-NVO was carried out through Ex situ tests, such as XRD and XPS. This research contributes a unique perspective to the formulation of high-performance cathode materials for AZIBs.

Industrial Waste Derived Separators for Zn-Ion Batteries Achieve Homogeneous Zn(002) Deposition Through Low Chemical Affinity Effects.

Designing a cost-effective and multifunctional separator that ensures dendrite-free and stable Zn metal anode remains a significant challenge. Herein, a multifunctional cellulose-based separator is presented consisting of industrial waste-fly ash particles and cellulose nanofiber using a facile solution-coating method. The resulting fly ash-cellulose (FACNF) separators enable a high ion conductivity (5.76 mS cm-1 ) and low desolvation energy barrier of hydrated Zn2+ . These features facilitate fast ion transfer kinetics and inhibit water-induced side reactions. Furthermore, experimental results and theoretical simulations confirm that the presence of fly ash particles in FACNF separators effectively accommodate the preferential deposition of Zn(002) planes, due to the weak chemical affinity between Zn(002) plane and fly ash, to mitigate dendrite formation and growth. Consequently, the utilization of FACNF separators causes an impressive cycling performance in both Zn||Zn symmetric cells (1600 h at 2 mA cm-2 /1 mAh cm-2 ) and Zn||(NH4 )2 V10 O25 (NVO) full cells (4000 cycles with the capacity retention of 92.1% at 5 A g-1 ). Furthermore, the assembled pouch cells can steadily support digital thermometer over two months without generating gas and volume expansion. This work provides new insights for achieving crystallographic uniformity in Zn anodes and realizing cost-effective and long-lasting aqueous zinc-ion batteries (AZIBs).

Defect engineered N-S codoped TiO2 nanoparticles for photocatalytic and optical limiting applications: Experimental and DFT insights.

N-S codoped TiO2 nanoparticles (NPs) were synthesized using a sol-gel cum hydrothermal approach, with ammonium sulfate as the nitrogen and sulfur source compound. The calcination temperature was varied from 500 to 700 °C. The pristine samples exhibited a mixed phase of anatase and brookite, while the doped samples exhibited only the anatase phase, as confirmed by X-ray diffraction (XRD) analysis. Fourier-transform infrared spectroscopy (FTIR) confirmed the presence of N-H vibrations and S-O bidentate complexation with Ti4+ ions. Electron paramagnetic resonance (EPR) revealed the presence of Ti3+ signals, confirming the creation of oxygen defects in the doped samples. The absorption and emission properties of the samples were investigated using ultraviolet-visible (UV-Vis) and photoluminescence (PL) spectroscopy. Vibrating sample magnetometry (VSM) analysis confirms the room-temperature ferromagnetic behavior of the N-S doped TiO2, which was attributed to the presence of oxygen vacancies, as evidenced by the EPR and PL results. The N-S doped TiO2 samples demonstrated superior photocatalytic degradation of Rhodamine B (RhB), Methylene Blue (MB), and Congo Red (CR) dyes under visible light illumination compared to the pristine TiO2. This enhanced performance was attributed to the presence of N and S dopants in TiO2, which create new energy levels within the band structure of TiO2, allowing for efficient absorption of visible light and subsequent generation of reactive species for dye degradation. N-S doping modifies the electronic structure of TiO2, enhancing two-photon absorption (TPA). This increased TPA efficiency suggests promising applications in optical devices, such as laser protection systems and optical limiters. Density Functional Theory (DFT) investigation also confirms that the presence of oxygen vacancies generates energy states below the conduction band. This, in turn, benefits the absorption of more visible light during photocatalytic activities and leads to a notable nonlinear absorption in optical limiting. Overall, the N-S doping strategy significantly improves the photocatalytic and optical limiting performance of TiO2 NPs, making them promising candidates for a wide range of applications.

Constructing stable V2O5/V6O13 heterostructure interface with fast Zn2+ diffusion kinetics for ultralong lifespan zinc-ion batteries.

Given their plentiful reserves, impressive safety features, and economical pricing, aqueous zinc - ion batteries (ZIBs) have positioned themselves as strong competitors to lithium - ion batteries. Yet, the scarcity of available cathode materials poses a challenge to their continued development. In this study, a V2O5/V6O13 heterostructure has been synthesized using a one - pot hydrothermal approach and employed as the cathode material for ZIBs. As evidenced by both experimental and theoretical findings, V2O5/V6O13 heterostructure delivers a rapid electrons and ions diffusion kinetics promoted by the stable interface and strong electronic coupling with significant charge transfer between V2O5 and V6O13, as well as a stable interface achieved by adjusting V - O bond length. Consequently, the optimized V2O5/V6O13 heterostructure cathode of ZIBs demonstrates exceptional capacity (338 mAh g-1 at 0.1 A g-1), remarkable cycling stability (92.96 % retained after 1400 cycles at 1 A g-1). Through comprehensive theoretical calculations and ex situ characterization, the kinetic analysis and storage mechanism of Zn2+ are thoroughly investigated, providing a solid theoretical foundation for the advancement of novel V - based cathode materials aimed at enhancing the performance of ZIBs.

Architecting a High-Energy-Density Rocking-Chair Zinc-Ion Batteries via Carbon-Wrapped Vanadium Dioxide.

Aqueous zinc-ion batteries (ZIBs) show great potential in large-scale energy storage applications because of their low cost and high safety features, whereas the inefficient zinc utilization and uncontrollable dendrite issue of the zinc metal anode greatly limit their energy density and cycling stability. Herein, a carbon-wrapped vanadium dioxide (VO2@C) core-shell composite has been prepared and utilized as an intercalated anode of "rocking-chair" ZIBs. Benefiting from the carbon shell, the charge transfer and structural stability of VO2@C have been significantly improved, thus delivering a specific capacity of 425 mA h g-1 at 0.1 A g-1 and a capacity retention of 94.9% after 3000 cycles at 5 A g-1, better than that of VO2 (338 mA h g-1 and 59.2%). Further, the low Zn2+ intercalated potential (0.54 V vs Zn2+/Zn) and reversible Zn2+ intercalation/deintercalation behavior of VO2@C enable the successful construction of VO2@C||ZnMn2O4 "rocking-chair" ZIBs, which achieve a capacity of 104 mA h g-1 at 0.1 A g-1 and an exceptional energy density of 96.3 W h kg-1 at 74.1 W kg-1 (based on the total weight). This research enriches the currently available options for constructing high-energy-density energy storage systems.

Zn salts incorporated polyurethane/polyacrylonitrile electrospinning fiber membrane for high porosity polymer electrolyte in Zn ion battery.

So far, a large variety of polymer molecule architectures have been explored in the electrolyte field. Polymer electrolytes have gathered research efforts as an interesting alternative to conventional liquid electrolytes due to their advantages of low probability of leakage and low volatility of liquid solvent, lightweight, flexibility, inertness, high durability, and thermal stability. In this work, a polymer electrolyte developed from a polyurethane/polyacrylonitrile (PU/PAN) electrospinning fiber membrane was added with different zinc (Zn) salts, namely, Zn(CH3CO2)2, ZnSO4, and Zn(OTf)2. The samples with the Zn salt presented many different properties; especially, the high Zn(OTf)2 sample showed gradually bundle morphology in its structure. Characterization revealed improved properties in contact angle, water uptake, and thermal resistance. Namely, the 15 wt% Zn(OTf)2) sample exhibited an outstandingly high ionic conductivity of 3.671 mS cm-1, which is 10 times higher than that of the neat PU/PAN membrane.

Highly Reversible Zn Metal Anode with Low Voltage Hysteresis Enabled by Tannic Acid Chemistry.

The zinc dendrites and side reactions formed on the zinc anode have greatly hindered the development of aqueous zinc-ion batteries (ZIBs). Herein, we introduce tannic acid (TA) as an additive in the ZnSO4 (ZSO) electrolyte to enhance the reversible Zn plating/stripping behavior. TA molecules are found to adsorb onto the zinc surface, forming a passivation layer and replacing some of the H2O molecules in the Zn2+ solvation sheath to form the [Zn(H2O)6-xTAx]2+ complex; this process effectively prevents side reactions. Moreover, the lower desolvation energy barrier of the [Zn(H2O)6-xTAx]2+ structure facilitates uniform Zn metal deposition and enables a stable plating/stripping lifespan of 2500 h with low voltage hysteresis (53 mV at 0.5 mA cm-2) as compared to the ZSO electrolyte (167 h and 104 mV). Additionally, the incorporation of the MnO2 cathode in the TA + ZSO electrolyte shows improved cycling capacity retention, from 64% (ZSO) to 85% (TA + ZSO), after 250 cycles at 1 A g-1, demonstrating the effectiveness of the TA additive in enhancing the performance of ZIBs.

Interfacial Reconstruction for Regulating Zn2+ Deposition toward Ultrastable Zn Metal Anodes.

Rechargeable aqueous zinc-ion batteries (AZIBs) are attracting much attention as high-density energy storage systems owing to their fascinating features with low cost, high safety, and simple manufacturing process. However, the commercialization of Zn anodes is hindered by uncontrollable dendrite growth and water-induced side reactions. Herein, a spontaneous reconstruction of a honeycomb-structural hopeite layer (ZPO) on a Zn metal anode (Zn@ZPO) is rationally developed as a functional protection interface by the liquid-phase deposition strategy. The formed ZPO layer not only promotes ion/charge transport and restrains Zn corrosion but also modulates the preferred deposition orientation of the Zn(002) nanosheet for the dendrite-free Zn anode. Accordingly, the Zn@ZPO symmetric cell exhibits satisfactory cycle lifespans of 1500 h at 1 mA·cm-2/1 mAh·cm-2 and 1400 h at 5 mA m-2/1 mAh·cm-2. When assembled with the (NH4)2V10O25·8H2O (NVO) cathode, the Zn@ZPO||NVO full cell delivers an ultrastable cycling lifespan for 25 000 cycles with a discharge capacity retention of 86.6% at 5 A·g-1. Therefore, this work will pave a novel avenue for constructing dendrite-free AZIBs.

Reconstructing the Anode Interface and Solvation Shell for Reversible Zinc Anodes.

The attractive advantages of the Zn metal anode and water-based electrolyte, such as inherent safety and low cost, endow the zinc-ion batteries (ZIBs) with great potential in the future energy storage market. However, the severe surface side reactions and dendrites affect the service lifespan and electrochemical performance of ZIBs. Herein, a bifunctional electrolyte additive, l-ascorbic acid sodium (LAA), has been added into ZnSO4 (ZSO) electrolyte (ZSO + LAA) to settle the above issues of ZIBs. On the one hand, the LAA additive tends to adsorb on the Zn anode surface to generate a H2O-resistive passivation layer, which can effectively isolate the H2O corrosion and regulate the Zn2+ ion 3D diffusion, thus inducing a uniform deposition layer. On the other hand, the strong adsorption capacity between LAA and Zn2+ can transform the solvated [Zn(H2O)6]2+ into [Zn(H2O)4LAA], thus reducing the coordinated H2O molecules and further suppressing side reactions. With this synergy effect, the Zn/Zn symmetric battery with the ZSO + LAA electrolyte can deliver a cycle life of 1200 h under 1 mA cm-2, and the Zn/Ti battery also presents an ultrahigh Coulombic efficiency of 99.16% under 1 mA cm-2, greatly superior to the batteries with the ZSO electrolyte. Additionally, the effectiveness of the LAA additive can be further verified in the Zn/MnO2 full battery and pouch cell.

Ion Co-storage in Porous Organic Frameworks through On-site Coulomb Interactions for High Energy and Power Density Batteries.

Fast and continuous ion insertion is blocked in the common electrodes operating with widely accepted single-ion storage mechanism, primarily due to Coulomb repulsion between the same ions. It results in an irreconcilable conflict between capacity and rate performance. Herein, we designed a porous organic framework with novel multiple-ion co-storage modes, including PF6 - /Li+ , OTF- /Mg2+ , and OTF- /Zn2+ co-storage. The Coulomb interactions between cationic and anionic carriers in the framework can significantly promote electrode kinetics, by rejuvenating fast ion carrier migration toward framework interior. Consequently, the framework via PF6 - /Li+ co-storage mode shows a high energy density of 878 Wh kg-1 cycled more than 20 000 cycles, with an excellent power density of 28 kW kg-1 that is already comparable to commercial supercapacitors. The both greatly improved energy and power densities via the co-storage mode may pave a way for exploring new electrodes that are not available from common single-ion electrodes.

2D Transition Metal Dichalcogenides for Photocatalysis.

Two-dimensional (2D) transition metal dichalcogenides (TMDs), a rising star in the post-graphene era, are fundamentally and technologically intriguing for photocatalysis. Their extraordinary electronic, optical, and chemical properties endow them as promising materials for effectively harvesting light and catalyzing the redox reaction in photocatalysis. Here, we present a tutorial-style review of the field of 2D TMDs for photocatalysis to educate researchers (especially the new-comers), which begins with a brief introduction of the fundamentals of 2D TMDs and photocatalysis along with the synthesis of this type of material, then look deeply into the merits of 2D TMDs as co-catalysts and active photocatalysts, followed by an overview of the challenges and corresponding strategies of 2D TMDs for photocatalysis, and finally look ahead this topic.

Designing a Built-In Electric Field for Efficient Energy Electrocatalysis.

To utilize intermittent renewable energy as well as achieve the goals of peak carbon dioxide emissions and carbon neutrality, various electrocatalytic devices have been developed. However, the electrocatalytic reactions, e.g., hydrogen evolution reaction/oxygen evolution reaction in overall water splitting, polysulfide conversion in lithium-sulfur batteries, formation/decomposition of lithium peroxide in lithium-oxygen batteries, and nitrate reduction reaction to degrade sewage, suffer from sluggish kinetics caused by multielectron transfer processes. Owing to the merits of accelerated charge transport, optimized adsorption/desorption of intermediates, raised conductivity, regulation of the reaction microenvironment, as well as ease to combine with geometric characteristics, the built-in electric field (BIEF) is expected to overcome the above problems. Here, we give a Review about the very recent progress of BIEF for efficient energy electrocatalysis. First, the construction strategies and the characterization methods (qualitative and quantitative analysis) of BIEF are summarized. Then, the up-to-date overviews of BIEF engineering in electrocatalysis, with attention on the electron structure optimization and reaction microenvironment modulation, are analyzed and discussed in detail. In the end, the challenges and perspectives of BIEF engineering are proposed. This Review gives a deep understanding on the design of electrocatalysts with BIEF for next-generation energy storage and electrocatalytic devices.

High electrolyte uptake of MXene integrated membrane separators for Zn-ion batteries.

The recent development of separators with high flexibility, high electrolyte uptake, and ionic conductivity for batteries have gained considerable attention. However, studies on composite separators with the aforementioned properties for aqueous electrolytes in Zn-ion batteries are limited. In this research, a polyacrylonitrile (PAN)/bio-based polyurethane (PU)/Ti3C2Tx MXene composite membrane was fabricated using an electrospinning technique. Ti3C2 MXene was embedded in fibers and formed a spindle-like structure. With Ti3C2Tx MXene, the electrolyte uptake and ionic conductivity reached the superior values of 2214% and 3.35 × 10-3 S cm-1, respectively. The composite membrane presented an excellent charge-discharge stability when assembled in a Zn//Zn symmetrical battery. Moreover, the developed separator exhibited a high flexibility and no dimensional and structural changes after heat treatment, which resulted in the high-performance separator for the Zn-ion battery. Overall, the PAN/bio-based PU/Ti3C2Tx MXene composite membrane can be potentially used as a high-performance separator for Zn-ion batteries.

Understanding the Catalytic Kinetics of Polysulfide Redox Reactions on Transition Metal Compounds in Li-S Batteries.

Because of their high energy density, low cost, and environmental friendliness, lithium-sulfur (Li-S) batteries are one of the potential candidates for the next-generation energy-storage devices. However, they have been troubled by sluggish reaction kinetics for the insoluble Li2S product and capacity degradation because of the severe shuttle effect of polysulfides. These problems have been overcome by introducing transition metal compounds (TMCs) as catalysts into the interlayer of modified separator or sulfur host. This review first introduces the mechanism of sulfur redox reactions. The methods for studying TMC catalysts in Li-S batteries are provided. Then, the recent advances of TMCs (such as metal oxides, metal sulfides, metal selenides, metal nitrides, metal phosphides, metal carbides, metal borides, and heterostructures) as catalysts and some helpful design and modulation strategies in Li-S batteries are highlighted and summarized. At last, future opportunities toward TMC catalysts in Li-S batteries are presented.

Sputter-Deposited Binder-Free Nanopyramidal Cr/γ-Mo2N TFEs for High-Performance Supercapacitors.

Due to their outstanding power density, long cycle life and low cost, supercapacitors have gained much interest. As for supercapacitor electrodes, molybdenum nitrides show promising potential. Molybdenum nitrides, however, are mainly prepared as nanopowders via a chemical route and require binders for the manufacture of electrodes. Such electrodes can impair the performance of supercapacitors. Herein, binder-free chromium (Cr)-doped molybdenum nitride (Mo2N) TFEs having different Cr concentrations are prepared via a reactive co-sputtering technique. The Cr-doped Mo2N films prepared have a cubic phase structure of γ-Mo2N with a minor shift in the (111) plane. While un-doped Mo2N films exhibit a spherical morphology, Cr-doped Mo2N films demonstrate a clear pyramid-like surface morphology. The developed Cr-doped Mo2N films contain 0-7.9 at.% of Cr in Mo2N lattice. A supercapacitor using a Cr-doped Mo2N electrode having the highest concentration of Cr reveals maximum areal capacity of 2780 mC/cm2, which is much higher than that of an un-doped Mo2N electrode (110 mC/cm2). Furthermore, the Cr-doped Mo2N electrode demonstrates excellent cycling stability, achieving ~ 94.6% capacity retention for about 2000 cycles. The reactive co-sputtering proves to be a suitable technique for fabrication of binder-free TFEs for high-performance energy storage device applications.

Microplastics in the environment: Recent developments in characteristic, occurrence, identification and ecological risk.

Microplastics (MPs) are developing as persistent pollutants that are causing significant concern in terms of environmental health. A microplastic is a particle of plastic that is less than 5 mm in diameter, which has penetrated and harmed the environment. MPs have been the subject of numerous analyses, including several adverse assessments; however, most of these studies have focused on their presence in coastal environments. The current state of knowledge regarding the characteristics, occurrences, and potential impact of MPs in the terrestrial ecosystem is incomplete. The goal of this study is to undertake a thorough review of existing knowledge and scientific publications on MP occurrences in the environment, their fate and mobility, and their consequences, as well as to explore such discoveries. MPs have been elaborately discussed in this review in terms of their occurrences, features, and origins in the oceans, freshwater, sediments, soils, and the atmosphere, along with the data obtained from experiments and models on the fate and mobility of MPs in the environment. This paper also includes research data on the environmental toxicity, bioavailability, and bioaccumulation of MPs.

Boosting Zn2+ Diffusion via Tunnel-Type Hydrogen Vanadium Bronze for High-Performance Zinc Ion Batteries.

Aqueous zinc ion batteries (ZIBs) are emerging as a promising candidate in the post-lithium ion battery era, while the limited choice of cathode materials plagues their further development, especially the tunnel-type cathode materials with high electrochemical performance. Here, a tunnel-type vanadium-based compound based on hydrogen vanadium bronze (HxV2O5) microspheres has been fabricated and employed as the cathode for fast Zn2+ ions' intercalation/deintercalation, which delivers an excellent capacity (425 mAh g-1 at 0.1 A g-1), a remarkable cyclability (91.3% after 5000 cycles at 20 A g-1), and a sufficient energy density (311.5 Wh kg-1). As revealed by the experimental and theoretical results, such excellent electrochemical performance is confirmed to result from the fast ions/electrons diffusion kinetics promoted by the unique tunnel structure (3.7 × 4.22 Å2, along the c direction), which accomplishes a low Zn2+ ion diffusion barrier and the superior electron-transfer capability of HxV2O5. These results shed light on designing tunnel-type vanadium-based compounds to boost the prosperous development of Zn2+ ion storage cathodes.

Non-invasive electrochemical immunosensor for sweat cortisol based on L-cys/AuNPs/ MXene modified thread electrode.

Thread-based electrochemical immunosensor is fabricated for non-invasive detection of cortisol in sweat by immobilization of anti-cortisol on L-cys/AuNPs/MXene modified conductive thread electrode. MXene and AuNPs increase the surface area of conductive thread electrode and facilitate anti-cortisol immobilization leading to enhanced sensor sensitivity. Anti-cortisol is immobilized on L-cys/AuNPs/MXene modified electrode by using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide and N-hydroxysulfosuccinimide coupling agents. The electrochemical detection of cortisol is based on the decrease of oxidation current towards the antigen-antibody binding interaction owing to blocking of electron transfer process by cortisol. Under the optimal conditions, this immunosensor offers high sensitivity, a wide linearity of 5-180 ng mL-1 and a detection limit of 0.54 ng mL-1 with negligible effect from interferences. Furthermore, this immunosensor provides high reproducibility and long-term storage stability (≥6 weeks). Ultimately, this system is successfully applied for the detection of cortisol in artificial sweat with satisfactory results. Hence, this platform might be suitable to apply as a wearable electrochemical sensor for sweat cortisol by integrating on a wristband.

Occurrences and removal of pharmaceutical and personal care products from aquatic systems using advanced treatment- A review.

Pharmaceuticals, personal care items, steroid hormones, and agrochemicals are among the synthetic and indigenous products that make up micropollutants, also known as emerging contaminants. Pharmaceutical and personal care products (PPPs) are a class of developing micropollutants that can harm living organisms even at low concentrations. Many are detected in surface water and wastewater from the treatment process, with quantities ranging from ng L-1 to gL-1; however, residual PPPs at dangerously high levels have indeed recently been recognized in the ecosystem. Residential sewage treatment plant (STP) dump the largest majority of these pollutants into the environment on a regular basis. As a result of its robust structure, it has a longer lifespan in the environment. This review article discusses how surface water pollutants such pesticides, petroleum hydrocarbons, and perfluorinated compounds affect water quality, as well as the most cost-effective adsorbents for removing these PPPs. The goal of this study is to provide information about the origins of PPP, as well as diagnostic procedures and treatment options. Research on developing contaminants is also aimed at evaluating the efficacy and affordability of adsorption.